john: thank you, terry anderson, may joules. coming up, the return to my local park. why is it so nice and so many are a mess? up next, how clever ways to mark property helped make america rich. ♪ john: now, i want to introduce you to one of the most impressive people i know. i first met in maybe 15 years ago, one of those lunches. ideas about solving poverty. i go to lunch is like that because it bugs me that america is so rich when most of the world's poor and the world is not figured out a way to give them what it was that gave us power to prosper. so i go to lunch. i'm skeptical, but there since hernando de soto of the institute for liberty and democracy, a think tank based in peru. he starts pulling these pictures out of his briefcase, pictures that show slum dwellings built on top of each other, much like this. he went on to explain, well, i will let you explain it. what to these pictures show? >> they show that roughly about 4 billion people in the world actually build their homes and all their businesses outside the legal system. it's all haphazard and disor